Wrench for spark plugs and the like



Dec. 8, 1942. H, MERRlMAN ETAL' 4 2,304,271

WRENCH FOR SPARK PLUGS AND THE LIKE Filed Sept. 9, 1940 IN VE N TOR. Nerf/777a BY .ORNEYS Patented Dec. 8, 1942 WRENCH FOR SPARK PLUGS AND THE LIKE Henry H. Merriman and Clifford D. Burbank,

Jackson, Mioh., assignors to Mechanics EngineeringCompany, Jackson, Mich.

UNITED STATE Application September 9, 1940, Serial No. 356,012

' 10 Claims.

The main objects of this invention are: First, to provide a wrench by means of which spark plugs and the like may be quickly and easily removed'from or inserted in an engine with little likelihood of injury Second, to provide a wrench of this character which protects the porcelain and other parts of a spark plug which are likely to be broken or injured and also facilitates the removal and replacement of the spark plugs and constitutes a holder'thereior while thespark plug is being cleaned.

Third, to provide a wrench having these advantages which is simple and economical in its parts and very durable.

Objects "relating to details and'economies of the invention will appear from thedescription to follow. The invention is defined and pointed out in the claims." I 7 Preferred embodiments of the invention are illustrated in the accompanying drawing, in which: 7

Fig. l is a longitudinal section of a spark plug wrench embodying the invention with a spark plug in position therein.

Fig. 2 is a view correspondingto that of Fig. '1

with the spark plug removed.

Fig. 3 is a side view-of gripping and supporting fingers assembledas a unit with the supporting'member.

Fig. 4 is an enlarged detail section on line of Fig.3.

Fig. 5 is a fragmentary longitudinal section of a modified form or embodiment of the invention. Fig. 6 is a side view of a modified form of spring finger assembly formed of wire.

Fig. '7 is a fragmentary view of a still further modification or embodiment of the invention. Our present-invention is in certain respects an improvement upon the invention, the subject matter of the Merriman application'for Letters Patent, Serial No. 339,653, filed June 10, 1940.

We have not illustrated the handle of our wrench but ourimproved socket or body member I, illustrated in Figs. 1 and 2, has a socket 2 at its inner end adapted to receive the shank or spindle of a handle or actuating member and has aligned transverse bores 3 adapted to receive a transversely disposed shank of a handle. 7'

At its inner end, the tubular body member I is provided with' a non-circular socket 4 adapted to receive the non-circular portion 5 of a spark plug 6. This body member is provided with aninternal annular rib I at the inner end of the socket 4' andpreferably has a conical recess 8 to the spark plug. 7

the spring-spark plug above this rib. The body member also has an internal annular shoulder 9 adjacent its inner end.

III which are supported to engage a spark plug.

as indicated in Fig. 1. These spring-fingersare mounted at their inner ends on an annular support II, this support having recesses. 12 in the periphery thereof receiving the ends 13 of the spring-fingers which are retained therein .by upsetting the metal at M, see-Fig. 4.'-

The member I l is mounted for axial movement within the body member-that is, it'is. axially slidable therein, the Spring fingers, asstated, being inwardly bowed, there being in'the preferred embodiment rather sharp bowing ofisets l5 adjacent'the outer ends of the fingers, the'outer ends'lB'of the lingers being laterally directed and are seated on the rib "1' and have supporting engagement with the rib 'l within the recess 8.

The coiled spring I! is arranged in'thrust engagement with the shoulder 9 andacts upon the support II to urge the sameoutwardly and urges the ends of the'fing'ers' against the rib 1.

It will be observed by'reference to Fig! -1 that when a spark plug is engaged withinthe wrench, the bowed portions oi pressed outwardly, and owing "to the ends of the fingers being in thru's't engagementwith the rib 1, the upper ends of the fingersare urged upwardly against the thrust of the spring l1. This avoids the necessity of a "distorting bowing of the spring fingers. g v e The structure is highly effective in Supporting the spark plug. so that the porcelain or'frangibl'e' portion thereof indicated at i8 is yieldably up-f ported and cannot. come into contactwiththe; walls of the Wrench, 7 Also, they serve to keep the spark plug, centered in thesocketior effective guidance, of the [spark plug and inin erting it. The wrench serves as an efiectlve' means for supporting the spark plug while it is being cleaned and minimizes the handlingand consequent liabilityto breakage or damage. It greatly .facilitates not only theplaceme t of thespark plugs in the original assembly but is more particularly advantageous in the removal and cleaning and replacement of the spark plugs.

It willbe observed that the inwardofisetsjl of the spring fingersare positioned soa's to, em

gage below .the annular rib 20 on the porcelain portion 0f v the spark plug, the spark plug illustrated being quite widely used. .However, there IS an effective gripping and supporting actionon variously Qshap'ed sizes of. spairkirlugs-thatlis,

We provide a plurality of bladespring fingers so far as the frangible porcelain portions thereof are concerned. It will be understood of course that the wrench members must have sockets suitable for the particular sizes of spark plugs so far as their wrench receiving portions are concerned.

In the embodiment of our invention shown in Fig. 5, the thrust spring I! is omitted and the support 2| corresponding to the support II is seated directly against a shoulder 22, the ends of the spring fingers 23 being in supporting engagement with the internal shoulder 24. In this spring fingers having inward ofisets adjacent their outer ends, a support to which the inner ends of said fingers are fixedly secured axially slidable Within said body member, and a thrust spring acting to urge said support and the spring fingers carried thereby outwardly, said body member having an internal annular shoulder constituting a seat for said thrust spring and an annularrib constituting a support for the laterally directed outer ends of said spring fingers and a stop for a spark plug within said socket,

embodiment, the spring members 23 will yield'or sprin in themselves when th spark plug is introduced. As in the embodiment of Figs. ls-4,

the springs 23 are secured to support 2| for'insertion therewith as a unit in the wrench body member.

In the embodiment shown in Fig. 7, the support member 25 is seated against the shoulder 26 and is retained in that position by-means of the split ring 21'which engages in an annular recess or groove 28 in the wall of the wrench member" and in a groove 29 in the support member. In

this case, the spring fingers 30 are appropriately. secured to support 25 and may move downward so that the;kink,-.

ly when a spark plug is inserted ing action thereof is not necessary.

In Fig. 6, we illustrate astructure in which the spring fingers 3| are formed of wire suitably offset at 32 to engage a spark plug. In this case, the

thrust spring 33 is formed integrally with the spring fingers-that is, the wire forming the spring fingers is formed into coils to provide the thrust spring 33. The action is the same as that ofthe embodimentshown in Figs. 1 and 2:

It will be. observedthat in the embodimentshownin Figs. 1.and.2, the parts may be assembled by inserting. the spring I! and then inserting the unit consisting ofthe spring finger l0 and the support Il,,and compressing the. spring I! until the ends of the finger snap behind the supporting rib 1. r g i In assembling a unit such as shown in Fig. 6,

it is only necessary to insert it into the tubular body and compress the coiled spring portion 33 until the ends of the fingerssnap or spring be hind the supporting ledge.

In the embodiment shown in Fig- 5,- the unit consisting of the support 2| andthefingers ,23 are inserted in the body and the spring fingers bent or snapped behind the supporting shoulder.

In the embodiment shown in Fig. 7,1the unit consisting of the spring fingers 30 and the supporting element 25 with the ring2'lf engaged therein is pushed into the tubular body until the supporting member abuts the shoulder 26 and the retaining ring snaps into the groove 29.

In all of these embodiments, the parts are quite economical to produce and easily inserted.

, The structures are well adapted for'both new work and repair work and they are very desirable for use in service stations as our implements render rapid work possible. v p

We have not attempted to illustrate or describe other embodiments or embodiments of our invention as We believe the disclosure made will enable those skilled in the art to embody or adapt our improvements as may be desired.

Having thus described our invention, what we claim as new and desire to'secure by Letters Patent, is: 7

I. A Wrench member comprising a tubular body member adapted to receive the major por tion of a spark plug and having a, non-circular spark plug socket at its outer end, a plurality of said socket member having a conical recess above said rib receiving the ends of said fingers.

. 2. A Wrench member comprising a tubular body member adapted to receive the major portionof a spark plug and having a non-circular spark plug socket at its outer end, a plurality of outer endyth'ere' being an internal ribconstitut ing a stop for a spark plug at the innerendzot said socket, said ,bodymember having aconical recess above saidv rib and an annular shoulder in spaced relation to saidyrima plurality of in wardlybowed spring spark plug engaging fingers, a support. slidable within. said body member and to whichth'einner endsoi said fingers are se cured, and a spring seated on said shoulder and acting to urge said spring finger support outwardlsgtheouter ends-of said fingers being directed laterally into said recess and being in; end supporting engagement withsaid rib. 4.;A wrench comprisinga tubular body member adapted to receive the major portion-of 'a spark plug and having a spark plug. socket at its outer end, there being an internal rib constitute.

ing a stop for a, spark plug at the: inner end of said socket, said body .-member having an annular shoulder in spacedrelation to said ri b,-a plurality of inwardly bowed spring spark plug engaging fingers, a support slidable within said body member and to which the inner ends of said fingers, are secured, and;a spring seated on said shoulder andacting to urge said spring finger support outwardly, the outerendsof said fingers being in end supporting engagement with said 1'ib, V L. I

5. Inawrench, the combination of a tubular body adapted to receive the major portion. of a spark plug and having a non gers having inward. ofi'sets; adjacent their outer ends and laterally directed outer'ends, a support vfor said fingers disposed within; said body for movement axially thereof, and? a thrust sprin actingto urge said support 'outwardly, said body m r h vin an internal support for the outer ends of said springfingersy,

, v6. In a wrench,-the combination" of a tubular bodyadapted to spark lug and receive the major'porticn. ofa having a spark plug engaging socket at its outer end, a pluralityofspark plug' engaging fingers of springmaterial'mounted within said body. at the inside of said socket and circular spark plugsocket at its outer end, a plurality ofspring fin adapted to yieldably receive and retainingly grip a spark plug engaged by the socket, the inner ends of said spring fingers being yieldably supported by means acting to urge them outwardly, and thrust sustaining means within the body with which the outer ends of said fingers are engaged.

7. In a wrench, the combination of a tubular body member having a work socket at its outer end, a plurality of spring fingers disposed longitudinally within said body and having inwardly disposed work engaging offsets, means for supporting the inner ends of said fingers for movement longitudinally of the body, a stop means coacting with the outer ends of said fingers, and a thrust spring acting to urge said fingers against said stop means.

8. In a wrench, the combination of a tubular body member having a work socket at its outer end, and a plurality of inwardly bowed spring fingers disposed longitudinally within said body in opposed relation to yieldably grip work engaged within the socket and extending inwardly therefrom, the inner ends of said fingers being supported for limited axial movement within said body member and their outer ends being in lateral supported engagement with the wall of the body member.

9. A wrench comprising a chambered body member having a work receiving socket at its outer end, a plurality of inwardly bowed spring work engaging fingers disposed longitudinally within said body member, means for sustaining said fingers relative to the body member at one end of the fingers, and a spring sustained support for the other end of said fingers slidably mounted within said body member whereby the fingers are supported to yieldably engage the end of work projecting inwardly beyond the socket.

10. In a wrench, the combination of a chambered body member having a Work socket at its outer end, and a plurality of spring fingers disposed longitudinally within said body member and having inwardly disposed work engaging ofisets adjacent their outer ends, said fingers being sustained at one end thereof and having means yieldably supporting the same at the other, and being adapted to yieldably receive the outer end of the work intermediate said ends to yieldably support the work and prevent its coming into contact with the walls of the body member.

HENRY H. MERRIMAN. CLIFFORD D. BUR/BANK. 

